Re: No exceptions?
Date: Fri, 30 Jun 2006 09:58:55 +0200
Bob Badour wrote:
> The extend operation creates a new relation by adding an attribute to an
> existing one. Strictly speaking, whether the candidate key would be
> preserved depends on the operation used to derive the extended
> attributes. Ungrouping a relation valued attribute, for instance, would
> affect the key. However, most familiar extend operations would not.
-- JonReceived on Fri Jun 30 2006 - 09:58:55 CEST